Project description:In order to understand the contribution of autophagy and alternative NF-kappaB signalling to transcriptional output in A549 lung cancer cells, RNAi was used to knockdown the expression of core autophagy genes (ATG5, ULK1) or the key subunit of alternative NF-kappaB RELB. Seven samples were prepared for each biological replicate; two sequence independent non-targeting control siRNAs were transfected as a negative control. Three sequence independent siRNAs targeting the core autophagy machinery were transfected (ATG5 si, ATG5 si(2), ULK1 si). N.B. ATG5 si(2) only partially ablates Atg5 protein expression whereas ATG si has greater efficacy. Two sequence independent siRNAs targeting RELB were transfected (RELB si, RELB si(2) ). Three independent biological replicates of all conditions were obtained, by performance of the experiment on different days.
Project description:In order to understand the contribution of autophagy and alternative NF-kappaB signalling to transcriptional output in A549 lung cancer cells, RNAi was used to knockdown the expression of core autophagy genes (ATG5, ULK1) or the key subunit of alternative NF-kappaB RELB.
Project description:The NF-kappaB and p53 transcription factors control the expression of complex gene regulatory networks in response to many cell stresses and stimuli. This experiment describes gene expression profiling of cells depleted for EZH2, NF-kappaB2, RelB and p53. We find that EZH2 is the major effector of crosstalk between the alternative NF-kappaB and p53 pathways and acts to suppress cellular senescence. Total RNA was obtained from primary juvenile human dermal fibroblasts 48 hours after transfection with siRNA specific for one, or a targeted combination of the transcription factors, or a scrambled siRNA control.
Project description:NF-kappaB Activation Model includes the activation of both NFKB1:RELA and NFKB2:RELB for Canonical and Non-Canonical Pathway respectively.
The model includes the pathway model integrated with post-translational modifications of NF-kB subunits that regulate the NFKB1:RELA and NFKB2:RELB activity. The processes that are regulated by NF-kB pathway can be monitored through following readouts NFKB1:RELA Activity, NFKB2:RELB Activity, Degraded RelA, Degraded RelB, Degraded IkB, Degraded NIK, Apoptosis, Tumour, Antiviral Activity, B Cell Growth and Cell Migration. However, last 5 processes above are also influenced by other pathways too, therefore while making predictions, caution has to be exercised.
Project description:We uncovered an autophagic pathway regulating survival in ABC DLBCL upon BTK inhibition using genome wide CRISPR screening. To investigate the mechanism of action of this unique form of autophagy, we performed RNA-seq on TMD8 cells knocked out for various ATG genes that either showed resistance to BTK inhibitors (ATG9A, ATG101, ATG14, RB1CC1, WIPI2), those that did not (ATG5, ATG7, ULK1 and 2 DKO, or non-targetingcontrol), or TMD8 cells knocked out for the known NF-kB negative regulator TNFAIP3. Cells were treated for 24 hours with the BTK inhibitor, acalabrutinib, and gene expression signatures were calculated from normalized RNA-seq reads. We found NF-kB gene expression signatures to be downregulated in control cells upon BTK inhibition, but not in ATG KO cells conferring BTK inhibitor resistance.
Project description:We used proteomic profiling to identify proteins in the mTOR-autophagy axis. Mouse cell lines lacking individual autophagy genes (Atg5 or Ulk1/Ulk2) were treated with an mTOR inhibitor to induce autophagy and cultured in media with either glucose or galactose. Mass spectrometry proteome profiling revealed an elevation of both known autophagy proteins and candidates for new autophagy components.
Project description:Tristetraprolin (TTP) regulates inflammatory and immune responses by destabilizing target mRNAs via binding to their 3’-UTR AREs. However, we first found that TTP can regulate gene expression and alternative splicing of inflammatory and immune responses genes in the absence of stimulation. In order to find the regulatory mechanisms, we performed iRIP-seq experiments in HeLa cells. iRIP-seq study revealed that TTP binding sites are enriched in the CDS and intronic RNA regions. We also found that the TTP-targets genes were enriched in positive regulation of I-kappaB kinase/NF-kappaB cascade and positive regulation of NF-kappaB transcription factor activity pathway, such as STAT4, EGR3, RELB, TRIM22, RNF25, and TRAF1. Furthermore, we found that alternative splicing of the innate immune response genes were globally regulated by TTP in HeLa cells. Genome-wide mapping of TTP-RNA interactions now reveal that dominant TTP binding near a competing constitutive splice site, whereas prevalent binding close to an alternative site often causes intron retention. This positional effect was further demonstrated by disrupting a TTP-binding site on minigene constructs and detecting their AS events. These findings suggest a mechanism for TTP to modulate splice site competition to produce opposite functional consequences in HeLa cells.
Project description:Background: Lymphotoxin signaling via the lymphotoxin-β receptor (LTβR) has been implicated in several biological processes, ranging from development of secondary lymphoid organs, maintenance of splenic tissue, host defense against pathogens, autoimmunity, and lipid homeostasis. The major transcription factor that is activated by LTβR crosslinking is NF-κB. Two signaling pathways have been described that result in the activation of classical p50-RelA and alternative p52-RelB NF-κB heterodimers. Results: Using microarray analysis, we investigated the transcriptional response downstream of the LTβR in mouse embryoni fibroblasts (MEF) and its regulation by the RelA and RelB subunits of NF-κB. We describe novel LTβR-responsive genes that are regulated by RelA and/or RelB. Interestingly, we found that the majority of LTβR-regulated genes require the presence of both RelA and RelB, suggesting significant crosstalk between the two NF-κB activation pathways. Gene Ontology (GO) analysis confirmed that LTβR-NF-κB target genes are predominantly involved in the regulation of immune responses. However, other biological processes, such as apoptosis/cell death, cell cycle, angiogenesis, and taxis were also regulated by LTβR signaling. Moreover, we show that activation of the LTβR inhibits the expression of a key adipogenic transcription factor, peroxisome proliferator activated receptor-γ (pparg), suggesting that LTβR signaling may interfere with adipogenic differentiation. Conclusions: Thus, microarray analysis of LTβR-stimulated fibroblasts revealed further insight into the transcriptional response of LTβR signaling and its regulation by the NF-κB family members RelA and RelB. Keywords: cell type comparison (wt vs relA-/- vs relB-/-) after genetic modification using a time course for each cell type (wt, relA-/-, relB-/-) two time points were analysed (0h as control and 10h) using 3 technical replicates resulting in 18 samples in total
Project description:Background: Lymphotoxin signaling via the lymphotoxin-β receptor (LTβR) has been implicated in several biological processes, ranging from development of secondary lymphoid organs, maintenance of splenic tissue, host defense against pathogens, autoimmunity, and lipid homeostasis. The major transcription factor that is activated by LTβR crosslinking is NF-κB. Two signaling pathways have been described that result in the activation of classical p50-RelA and alternative p52-RelB NF-κB heterodimers. Results: Using microarray analysis, we investigated the transcriptional response downstream of the LTβR in mouse embryoni fibroblasts (MEF) and its regulation by the RelA and RelB subunits of NF-κB. We describe novel LTβR-responsive genes that are regulated by RelA and/or RelB. Interestingly, we found that the majority of LTβR-regulated genes require the presence of both RelA and RelB, suggesting significant crosstalk between the two NF-κB activation pathways. Gene Ontology (GO) analysis confirmed that LTβR-NF-κB target genes are predominantly involved in the regulation of immune responses. However, other biological processes, such as apoptosis/cell death, cell cycle, angiogenesis, and taxis were also regulated by LTβR signaling. Moreover, we show that activation of the LTβR inhibits the expression of a key adipogenic transcription factor, peroxisome proliferator activated receptor-γ (pparg), suggesting that LTβR signaling may interfere with adipogenic differentiation. Conclusions: Thus, microarray analysis of LTβR-stimulated fibroblasts revealed further insight into the transcriptional response of LTβR signaling and its regulation by the NF-κB family members RelA and RelB. Keywords: cell type comparison (wt vs relA-/- vs relB-/-) after genetic modification using a time course
Project description:Mechanisms of constitutive NF-kappaB signaling in multiple myeloma are unknown. An inhibitor of IkappaB kinase beta (IKKbeta), targeting the classical NF-kappaB pathway, was lethal to many myeloma cell lines. Several had elevated expression of NIK due to genomic alterations or enhanced protein stability while others had inactivating mutations or deletion of TRAF3. Both abnormalities triggered the classical and alternative NF-kappaB pathways. A majority of primary myeloma patient samples and cell lines had elevated NF-kappaB target gene expression, often associated with genetic and epigenetic alteration of NIK, TRAF3, CYLD, BIRC2/BIRC3, CD40, NFKB1, and NFKB2. These genetic and functional data demonstrate that addiction to the NF-kappaB pathway is a frequent feature of myeloma and suggest that IKKbeta inhibitors hold promise for the treatment of this disease. Keywords: time series design